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v3.10.0.1

Held for Sale and Discontinued Operations - (Details) - USD ($) $ / shares in Units, $ in Millions |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 28, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 28, 2017 | Dec. 31, 2017
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  |  |  | $ 0.0 | $ 1,131.0 |  |
Gain (loss) from sale of discontinued operations, net of tax |  |  | $ 554.3 | (17.2) | 552.7 |  |
Net (loss) income from discontinued operations |  | $ 0.0 | (15.2) | 0.0 | 20.5 |  |
OneBeacon |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Sale of stock, price per share | $ 18.10 |  |  |  |  | $ 18.10 |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold | $ 1,300.0 |  |  |  |  |  |
Gain (loss) from sale of discontinued operations, net of tax | $ 554.6 |  |  |  |  |  |
Net (loss) income from discontinued operations |  |  | (15.2) |  |  | $ 20.5 |
Discontinued Operations | OneBeacon |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Net (loss) income from discontinued operations |  |  | (15.2) |  | 20.5 |  |
Discontinued Operations | Tranzact |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Gain (loss) from sale of discontinued operations, net of tax |  |  |  |  | (1.0) |  |
Discontinued Operations | Sirius Group |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Gain (loss) from sale of discontinued operations, net of tax |  | (17.3) | (0.2) | 0.1 | (0.8) |  |
Net (loss) income from discontinued operations |  |  | $ 0.0 |  | $ 0.0 |  |
Connecticut | Discontinued Operations, Held-for-sale |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Assets held for sale |  | 3.3 |  | 3.3 |  |  | $ 3.3
Swedish Tax Authority | Discontinued Operations | Sirius Group |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Gain (loss) from sale of discontinued operations, net of tax |  | (17.3) |  | (17.2) |  |  |
Swedish Tax Authority | Sirius Group |  |  |  |  |  |  |
Discontinued Operations [Line Items} |  |  |  |  |  |  |
Loss contingency, estimate of possible loss |  | $ 17.3 |  | $ 17.3 |  |  |

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